This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The purpose of the study is to determine if individuals who are treated with HMG-CoA reductase inhibitors and develop myopathy have a higher prevalence of genetic mutations causing metabolic muscle diseases. Two-hundred patients will be recruited into the study.